Field of the Invention
The present invention relates to a cleaning head for cleaning a surface, such as a ship's hull. The cleaning head can also be used for cleaning a storage tank and other surfaces including a surface of a ship's lock door.
Description of Related Art
Offshore and marine industry, including transport by ships, involve large (steel) structures that are exposed to a wide range of conditions for relatively long periods of time. To secure a correct operation of these structures maintenance and care is important. For example, a ship's hull is fouled with marine organisms that increase the drag of the ship thereby increasing fuel consumption and engine wear, and decreasing the maneuverability of the ship. Already a small layer of fouling, such as a slime layer, is sufficient to cause aforementioned negative effects. In addition, the emission of gasses such as NOx, SOx and CO2 is increased by this fouling. Cleaning is mostly done in outside ports or in dry docks, or alternatively, to some extent during loading and unloading of the ship. As cleaning requires the removal of fouling on surfaces both under and above water, in practice ships are regularly subjected to cleaning and inspection. Similar cleaning and inspection is required for offshore structures, dry docks, and bridge columns.
In the field of cleaning devices for surfaces that are subject to the environment there are several types of cleaning robots, either remotely controlled or autonomous.
EP 1886904 discloses a climbing cleaning robot with high adherence magnets to attach to the metal surface, four drive wheels that are grouped in a rectangular configuration and a cleaning mechanism and the magnets located between the wheels. The magnets can be turned in an inactive state due to the connection of the magnets with a cylinder fixed to the chassis, which is able to move the magnets to the inactive state. Due to the specific configuration of the wheels in relation to the magnets and the cleaning mechanism, the robot is suited for flat surfaces instead of surfaces that are curved in three dimensions.
EP 1 216 761 discloses a device for hydrodynamic cleaning of surfaces. The device comprises a collector, a stator, a rotor comprising radial piping and high pressure-flow generators. The housing appears as a hollow shaped disk with at least one lower shaped surface and partially filled with a shifting ballast.
Relating to the attachment of a device to a surface, GB1270117 discloses a carriage or trolley for travel along an upright wall of magnetisable material. The device comprises magnetic means for attachment to the surface, that is kept at a fixed distance from the surface due to the runner wheels on the device.
The present invention has for its object to obviate or at least reduce the above stated problems.